System of automatic block-signaling for electric railways.



No. 884,158. I PATENTED APR. 7, 1908 W. K. HOWE.

SYSTEM OF AUTOMATIC BLOCK SIGNALING FOR ELECTRIC RAILWAYS.

APPLICATION FILED SEPT. 28 1906.

' 2 SHEETS-SHEET 1.

Q mvrml PATENTED APR. '7, 1908.

W. K. HOWE. I SYSTEM OF AUTOMATIC 121,001: SIGNALING FOR ELECTRICRAI-LWAYS.

APPLICATION FILED'SEPT. 28 190 6 2 SHEETS-SHEET z.

I WITNESSES: Mum *5 ATTORNEY WINTHROP K. HOWE, OF BUFFALO, NEW YORK,ASSIGNOR TO COMPANY, A CORPORATION OF NEW YORK.

SYSTEM OF AUTOMATIC BLOCK-SIGNALING FOR ELECTRIC RAILWAYS.

Specification of Letters Patent.

Patented April 7, 1908.

Application filed September 28, 1906. Serial No. 836,612

To all whomit may concern;

Be it known that I, WINTHROP KEITH HOWE, a citizen of the United States,residing at Buffalo, county of Erie, State of New York, have invented aSystem of Automatic Block-Signaling for Electric Railways, of'

which the following is a specification. i

My invention consists in new and useful improvements in systems ofautomaticb'lock signaling for electric railways.

' In the general practice of block signaling, the signals indicate 'toan approaching train the condition of the block ahead, both as to thepresence of another train in such block and as to the continuity of thetrafiic rails. In the application of block signaling to electricrailways in which cross bonding between tracks is a feature, :it issometimes convenient to employ two currents for signaling purposes ortwo portions of the same current. One of such currents flows down onerail and up the other, its purpose being to indicate the location of thecars, and the other current flows along both raiis in the samedirection, which I will call a-continuity current, and is employed toindicate any break or discontinuity 111'8. rail of. the track.

My invention relates to means for su )plyingthis continuity current tothe traclrway and to the devices actuated by such current to give therequired indications.

In the pract1ce of my invention, the continuity current is supplied tothe trackway where desired, by means of transformers,

Whose primaries are excited from thesource ofsignahng current, and whosesecondaries are in series with the ath 1n the propulsion current. Relaysare ikewise connected in series within the path of the propulsioncurrent. These relays are responsive both to the signaling current andto the propulsion current of the railway.

Figure 1' is a diagram illustrating the application of my invention toan electric railwailyg of the two-rail type, in which the traffic r bothact as returns for the' ropulsion current back to the generator. wotracks are shown, but the signaling devices are only complete in thecase of the block'sections X, Z, of one track. The two tracks arecross-bonded. Fig. 2 ,is' a diagram showing 'the. application of my sstem to an electric railway of the one-ra" type, in which a the twotrackways,

" single continuous rail ofeach track carries the propulsion currentback to the generator.

Referring to Fig. 1', D is the propulsioncurrent generator, which isshown as a direct current machine and connected'to an outgoing feederconductor 2. 3, 4, are the traffic rails divided into block sections X,Y, Z, by insulated-joints. A is an alternator supplying currents forsignaling to the distributing .mains 6 and 7. Transformers 8 supplysignaling current derived from these mains 6 and 7 to the block sectionsX, Y, Z. Said block sections are rendered continuous as to thepropulsion current, which is direct, and segregated as to the signalingcurrent,- which is alternating, by the react-ance bonds 9, which tiethetwo traffic rails together at the end of each block section, the rail4 being electrically continuous from one block section to the nextthrough the windings of relay 10 and the secondaries 11 of transformers12. Each transformer, 12, hasits primary 13 connected across the mains 6and 7 in series with the resistance 14. 15 is the track relay comprisingtwo stator coils 16, 17, and

a movable member 18. The signal 19 is operated by current derived fromthe battery 20, which normally flows through the contact 21 of relay 15,and the contact 22 of relay 10, and through thesolenoid 23, whichnormally holds signal 19 in the clear position. The relay 10 may bedesigned, so that it will become saturated by the propulsion current,for in such a case, it is obvious'tha't the flux produced will besufficient to hold the contact 22 closed. Similarly, the transformer 12may be designed so that it will begin to saturate for the same value ofthe propulsion current, as that which unaided would maintain the contact22 of the relay 1O closed. The corres onding trafiic rails of E Y, Z,and X, Y, Z, are connected together by the cross-bonds 24. 25 representsa break, .or electrical discontinuity in one of the traffic rails. Inthe operation of thisforin of my invention, it will be seen thattransformer 8 supplies current to a block section,'which flows forinstance down rail 3 and up rail 4. Such current backing up a ainst thereactance' of the coils 9 at the leftand end of the blocksecpotentialacross and -as there is a:

tion, produces a difference of the terminals of the coil 16,.

GENERAL RAILWAY SIGNAL difference of phase between the currents thecoils 16 and 17, a turning moment of the movable member 18 of the relayl5 will'be developed, normally closin the contact 21 in the absence of acar on t e block section, as in sections Y and Z. The relay will alsoremain closed, if there is no breakin'the -rail 4, the contact 22 beingheld closed by such current as flows "through the rail 4, either thepropulsion'current or the signalln current, or both, from thetransformers 8 and 12. The function of the transformer 12 is tosupplement the current supplied from the transformer 8. It will beseen'that the sec-- ondaries 11 of the transformers 12 are reversed inpolarity in adj'acentblock sections,

their (primaries 13 being connected inthe re-- verse manner across themains 6 and 7. The path of the currents in the cross-bonds, due to thetransformers 12, will, therefore,

- be as indicated ,by the arrows shown on con-- the secondaries 11 oftransformers 12 do not produce-a difference of potential across theductors 24. If the rail 4 is broken, as at 25 of section Z, even in theabsence of a car on the block section, both thepropulsion current andthe si naling current will be interrupted in the re ay 10, thus openingthe contact 22 and allowing the signal 19 to go to the dangerposition.'It will beseen that 15 and opening the contact 21, so as to send thesignal 19 to the danger position.

When a car 26 enters the block section (block section X) the currentfrom transformer 8 will be short-circuited' upon itself and divertedfrom the coil 16, thus denergizing relay 15, opening contact 21 andsending the signal 19 to the danger position.

In F i 2, the continuity current for rail 4 is supplie by a transformer27, whose primary 28, is connected across the signaling mains 6 and 7,and whose secondary 29, isinserted' direct-l in the cross-bondingconductor 24.

The re ay 10 is connected in series Withthe traffic rail 4, as inFig. 1. The winding 17 of the-relay15 is energized from a secondaf'y 30of a transformer 31, whose primary 32 is connected across the mains 6and 7. The said transformer has another secondary 33, which supplies thetrack circuit signaling current to the block section, as in Fig. 1 saidcurrent being designed to normally actuate the relay 15, by producing arotary field through the 'oint action of the currents of coils-16 and17.

he coil 16 is connected across a reactance- 34, which reactance isconnected in series with a resistance 35 across the traffic rails, 3,-

means.

in each b 4, of a block section. Thereactance is designed not tosaturate, by such'small amount'of propulsion'current, as due to leakageor other causes is allowed to flow through it by the limiting resistance35. It will be seen that the connections of the rimaries 28 are reversedsothat the polarity of these secondaries 29willbe diflerent in adjacentblock sections. The paths of the "currents in the. cross-bonds will,therefore, be shown bythe arrows. It will be seen that substantially thesame flow of continuity current occurs in the arrangement of Fig. 2, asthat of Fig. 1,

and,the operation of thesys tem is substantially the s'ame.

nfg out 'my invention, it will b'e evident that the continuity currentmay be sup lied'ina considerable number of ways :of transformers 27 ofadjacent b ock sections j wit ou't' departing from the spirit of myinvention, and I desire it to be understood that I am the first tosupply the continuity current locally to the traflic rails of anelectric I railway by means' of transformers or other transmittingdevices, or any suitable Furthermore, my invention is applicable to agreat variety oftypes of railway and to various arrangements ofreactance bonds and signaling circuits.

claim; v 1. A] signaling system comprising I an Having thus described myinvention, I

alternating generator, separate means connected'therewith arranged toproduce respectively a difierencelof, potential across the rails and acontinuity current along the rails ofa block section.

2. A signaling system compri singa single alternating generator,separate means con: nected, therewith arrangedto] produce respectively adifference of potential between t e rails, and to send a continuit-current I through therails, a relay connects with the rails toindicatethe condition of the block as to occupancy, and a relay arranged toindicate the condition of the .rails as to continuity.

'3. A signal ing system comprising an alternating generator, and meansconnected therewith arranged tocreate continuity currents in adjacenttrackways. I 4 I I 4. A signalingsystem comprising a signaling currentarranged to control a: track circuit and means in each'block forapplying 1 a local continuity current. p ,7

r 5. A signalingsyst'em comprising. means presence of a break in eithertrack rail.

6. A signaling system comprising av trans former connected'across thetrack railsand a transformer connected in series with a track rail ofeach section.

7 A signaling system comprising means whereby the traflic rails of eachblock siock for separately indicating the multaneously transmit thewhole propulsion-current, and two signaling currents.

8. A signaling system comprising a relay in each block sectiontraversedby the signaling current, and a relay traversed by the whole propulsioncurrent and the signaling currents.

9. A signaling system comprising means for impressing a signalingcurrent upon each block section, and means for causing a con tinuitycurrent to flow locally upon the block sections.

10. In a signaling system the combination of a transformer and a relayboth traversedby a propulsion current and adapted to be saturated byapproximately the same value of propulsion current. v

11. A signaling system comprising traflic rails divided into blocksections, both 'of said traffic rails conducting the propulsion currentfreely, one of such trafiic rails compris- 111%i11 its circuit reactancebonds, and the ot er of such traflic rails comprising in its circuitrelay devices and transformers.

12. A signaling system comprising a course of power current, a trackwaydivided into block sections, reactance bonds inter posed between theblock sections, means for exciting a difference of potential between therails of each block section, means for locally "bonds interposed betweensaid blocksections, said track rails forming a return for the powercurrent,- a source of signaling current, feeders therefrom, atransformer in each block section having its primary connected acrossthe alternating feeders and its secondary across the track, atransformer in each block section having its primary con nected acrossthe alternating feeders and its secondary in series with one rail ofadjacent block sections, a relay energized by the difference ofpotential between the rails, a

relay energized by the current flowing along a the rail. from one blocksection to the next,

and a signal controlled b said relays.

In testimony whereof, affix mysignature, in the presenceof twowitnesses.

WINTHROP K. HOWE.

. Witnesses:

A. F. DIETRIOK, El C. BEYER.

